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This short refracting telescope consists of two brass tubes. The inner one is engraved “Ramsden/London” and calibrated from one to four. The objective lens, 1 ¼ inches aperture is achromatic. There is a dial [not yet understood] that adjusts the eyepiece. The telescope is housed in a cylindrical cardboard container covered in shagreen.

Jesse Ramsden (1735-1800) was a prominent maker of mathematical and optical instruments who began in business in 1762, and was elected a Fellow of the Royal Society of London in 1786.